Filter.



E. ZAHM.

FILTER.

APPLICATION FILED DEC-28,1911- BENEWED JAN. 26, I917- Patented Mar. 13, 1917.

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FILTER.

APPLICATION FILED DEC. 28, I91]. RENEWED JAN. 26. I917.

1,21 8,738. Patented Mar. 13, 1917'.

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A 9 9 E M zjJaya/ 9 outrun srarns rarnur @FFKWR EDWARD ZAI-IM, OF BUFFALO, NEW YORK, ASSIGNOR T0 ZAHM MANUFACTURING COMPANY, OF BUFFALO, NEV] YORK, A. CORPORATION OF NEW YORK.

FILTER.

Specification of Letters Patent.

Application filed December 28, 1911, Serial No. 668,331. Renewed January 26, 1917. Serial No. 144,784.

To all whom it may concern:

Be it known that I, EDWARD ZAHM, a citizen of the United States, residing at Buffalo, in the county of Erie and State of New York, have invented new and useful Improvements in Filters, of which the follow-,

vided with a nozzlewhich was cemented to.

the tube and secured in an opening formed in a partition which separated the inlet and outlet chambers of the filter. This has been found objectionable on account of the tendency of the tube to become loose on the nozzle and thereby permit unfiltered liquid to pass from the unfiltered to the filtered side of the tube so that the quality of the filtered liquid was impaired or contaminated.

It is the purpose of this invention to provide improved means for securing the filter tubes to the nozzles in such manner that the tubes are not liable to become loose or detached from the nozzles and also to reinforce the filter tube adjacent to where the same is connected with the nozzle so that the tube is not liable to become broken at this place.

In the accompanying drawings consisting of 2 sheets: Figure 1 is a vertical longitudinal section of a filter embodying my invention. Fig. 2 is a fragmentary vertical section, on an enlarged scale, showing my improved means for connecting the outlet nozzle with the filter tube, also the means for reinforcing the filter tube and also the means for mounting a tube on the partition between the inlet and outlet chambers of the filter. Fig. 3 is a detached side elevation of the nozzle. 'Fig. 4 is a fragmentary longitudinal section of the outlet end of a filter tube and the reinforcing ferrule or sleeve mounted thereon. Fig. 5 is an end view of the filter tube, nozzle and reinforcing ferrule viewed from the outlet end thereof.

Similar characters of reference indicate corresponding parts throughout the several views. 7

In its general organization my improved filter comprises a cylindrical body 1 provided with a partition 2 which divides the interior of the body into an inlet chamber 3 and an outlet chamber 4, a front head 5- which is removablysecured to the front end of the body and closes the outer end of the inlet chamber, a rearhead 6 detachably secured to the rear end of the body and closing the outer end of the outlet chamber, a plurality of filter tubes 7 of porous material arranged within the inlet chamber and mounted-upon the partition so that the interior of each filter tube communicates with the outlet chamber, a supply pipe 8 for the unfiltered liquid connected with the inlet chamber, and a delivery pipe 9 for the fil- 1tOered liquid connected with the outlet cham- The liquid to be filtered enters through the supply pipe into the inlet chamber and passes thence inwardly through the pores of the several filter tubes and into the in terior thereof, thence, through the outlet of these tubes and through the partition into the outlet chamber and is then drawn ofi through the delivery pipe. As the liquid passes through the pores of the filter tubes the impurities contained therein are separated therefrom which impurities are retained on the outer side of the filter tubes and are removed therefrom at suitable intervals while the purified liquid passes the inner side of the filter tubes and is delivered to the outlet chamber and delivery pipe.

My improvements relate to the manner of mounting the filter tubes on the partition and are constructed as follows:

At the rear or outlet end of each filter tube its bore is provided with an internal screw thread 10 which is preferably formed by cutting this thread in the granular mate rial of the tube after the same has been molded and dried. At the outer'end ofthis tube the same is also provided with an annular rabbet 11 adjacent to the outer end of its internal thread which rabbet is also preferably out. If desired, however, the internal thread and the rabbet of the filter tube may Patented Mar. 13, 1917.

V of the filter.

and at its outer end this head is also be produced in the same at the time of molding the tube and while the same is in a plastic condition.

The means for mounting each filter tube on the partition and connecting the interior thereof with the outlet chamber of the filter comprise a nozzle, preferably of metal and having a contracted rear or outer neck 12 and an enlarged front or inner head 13 both of which are of tubular form. The periphery of the head is provided with an external screw thread 14: which engages with the internal screw thread of the filter tube provided with an external annular flange 15 which engages with the rabbet at the rear end of the filter tube. The nozzle flange 15 operates as a stop by engaging the bottom of the rabbet and limiting the extent which the head can be screwed into the filter tube and to permit of producing an end thrust of the nozzle against the filter tube for tightening the screw joint between the nozzle and filter tube. When the nozzle flange engages properly with the rabbet of the filter tube the rear or outer faces of the head and the flange of the nozzle are flush with the rear end of the filter tube.

By thus securing the nozzle to the filter tube by means of a screw joint these parts are reliably connected and all possibility of the filter tube becoming loose on the noz zle while using the filter or manipulating parts of the same is avoided.

To further insure a tight joint between the filter tube and the outlet nozzle a coment of any suitable kind may be placed in the screw joint between the head of the nozzle and the filter tube, thereby securely uniting the nozzle and filter tube and preventing any leakage through the joint betweenthe same. In the absence of a tight joint between these parts some of the unfiltered liquid on the outer side of the filter tube is liable to pass through the joint between the nozzle and tube and contaminate the filtered liquid on the inner side of the tube.

The contracted neck of each of the filter tubes projects rearwardly through an opening 16 in the partition of the filter body so that the interior of each filter tube is placed in communication with the outlet chamber 17 represents a packing or washer, preferably of rubber or other suitable elastic material, mounted on the neck of V the nozzle between the front side of the partition and the rear ends of the filter tube and nozzle head. A rearward pull is prothe partition from the inlet chamber to the outlet chamber of the filter and avoiding contamination of the filtered liquid in the outlet chamber by the admission of any unfiltered liquid.

The preferred means for thus clamping the platen between the nozzle andfilter tube and the front side of the partition consists of a clamping screw nut 18 engaging with an external screw thread 20 on the neck of the nozzle and bearing against the rear side of the partition by means of an interposedwasher 19, as shown in Figs. 1 and 2.

The front side of the packing preferably extends across the joint between the head of the nozzle and the filter tube, thereby further guarding against the passage of any unfiltered liquid from the inlet chamber into the interior of the filter tube through the joint between the latter and the nozzle.

Inasmuch as the removal of part of the stock at the rear end of each filter tube by the formation therein of the internal screw thread has a tendency to weaken the same, means are provided for reinforcing the filter tube at this end. The preferred means for this purpose comprises a reinforcing ferrule or sleeve 21 of metal which engages with the periphery of the filter tube at the rear or outlet end thereof. This ferrule may be secured to the filter tube solely by a driving or friction fit but the same is preferably additionally secured thereto by a coating of cement between these parts and also by scoring the bore of this ferrule, as shown at 22, Figs. 2 and l, so as to form a plurality of internal anchors for interlocking with the cement and holding the ferrule against displacement on the filter tube.

At its rear or outer end the ferrule is preferably provided with an internal annular flange 23 which engages with the rear end of the filter tube and serves as a stop to limit the extent which this ferrule may be pushed forwardly upon the tube. preferably of such length that when it is applied to the filter tube its front or inner end projects forwardly beyond the inner end of the nozzle head and the internally threaded part of the filter tube, as best shown in Figs. 2 and 4. By this means the reinforcing ferrule or sleeve embraces the filter tube where it is of fullthickness beyond where the same has been reduced in thickness by the formation of the screw thread therein, thereby strengthening the filter tube and compensating for the weakening effect due to the cutting of said thread.

lVhen cleaning each filter tube the outer side of the same is usually brushed to re move the scum or sediment therefrom and this repeated brushing causes the tube to gradually wear away. By extending the ferrule 21 forwardly beyond the front end of the nozzle head 13 the filter tube is pro- The ferrule is tected. at this region and guarded against being worn thin by the operation of brushing the same, thereby preserving its full thickness and strength at the connection between the same and the nozzle so that the tube is not liable to become broken while being handled.

I claim as my invention:

1. In a filter, the combination of a filter tube provided with an internal screw thread, an outlet nozzle provided with an external screw thread which engages with the thread of the filter tube and a ferrule surrounding that portion of the filter tube containing the nozzle and extending inwardly beyond the inner end of said nozzle and the internal thread of the filter tube.

2. In a filter, the combination of a filter tube having an internal screw thread and an annular rabbet at its outlet end, an outlet nozzle having an outer contracted neck and an inner enlarged head which is provided with an external screw thread engaging the internal thread of said tube and an external annular flange which engages with the rabternal screw thread, a nozzle having a neck secured in the opening of said partition and a head having an external screw thread which engages the thread of said tube, and a packing arranged around said neck between said partition and the head and tube and extending across the joint between said head and tube so as to simultaneously pack the joint between the neck and the partition and between the neck and the filter tube.

Witness my hand this 23rd day of December, 1911.

EDWARD ZAHM. Witnesses:

THEO. L.'POPP, ANNA Hnr'ers.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. O. 

